Torque Formula

What is Torque?

A measure of the amount of rotational force applied to an object is called torque. It describes the amount that a force acting on an object causes that object to rotate about an axis or pivot point.

Torque Formula 

Torque can be defined as the rotational effect of force on the axis of rotation. In a few words, it is said to be a moment of force. It is represented by τ.

The torque formula is given by

τ = F × d

Where,

  • Force applied = F

  • From the axis of rotation the perpendicular distance of force = d

The Magnitude of torque is given by

τ = Fd sin θ

  • Where θ is the angle between the applied force and the axis of rotation..

Units of Torque

The SI unit for torque is Newton-meter (Nm).It would be the value that would be a product of the force applied and its distance from the axis of rotation.

Solved Problems Based On Torque

Below are some questions on torque which gives an idea of how to calculate the terminologies related to torque.

Problem 1: The door is 40 cm in width. If it is released by exerting a force of 2N at its edge (away from the hinges).Calculate the torque produced which causes the door to open.

Answer:

Force applied = F = 2 N

Length of lever arm = d = 40cm

Torque = 0.40m as the distance amid the line of action of force and axis of rotation is 40 cm

Torque = F × d

             = 0.40 × 20

Torque = 8 Nm.

Problem 2: The Classroom door’s width is 50cm. If  the door handle  is 20cm from the edge and  5N of force is applied on the handle. Calculate the torque.

Answer:

The handle of the door is located at 20cm. Thus, the line of action is 20/2 = 10cm.

Length of  lever arm = d = 50 – 10 

                                       = 40cm

                                       = 0.4m

Force applied = 2N

Torque = F × d

            = 2 × 0.4

Torque = 0.8Nm.

Conclusion

The torque formula is an important tool; simultaneously, it assures keeping an eye on the rotational effect in physics or engineering. If one applies the formula appropriately, he should be able to design, analyze, and predict behavior for rotating systems and make sure the mechanical devices run efficiently.

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